Learning About Your Nervous System

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Nervous system

What does your nervous system do?

The nervous system includes the brain, the spinal cord, and all the nerves in your body. It controls:

  • Sight, hearing, taste, smell, and feeling (sensation).
  • Movement, balance, and coordination. It also controls the actions of most other body systems and processes such as digestion and blood flow.
  • Your ability to think and reason. It allows you to have thoughts, memories, and language.

The nervous system is divided into the brain and spinal cord (central nervous system) and the nerves that connect the spinal cord to other parts of the body (peripheral nervous system).

What problems can happen with your nervous system?

Nervous system problems may occur slowly. Bit by bit, they can cause you to lose control over something you used to do with ease. Problems also can occur quickly. These problems can be very dangerous. Symptoms may be mild or severe.

Examples of nervous system problems are:

  • Injuries. Most often, these are injuries to the head and spinal cord.
  • Mental health conditions, such as anxiety disorders or depression.
  • Diseases that cause a gradual loss of motor function. These include Parkinson's disease and multiple sclerosis (MS).
  • Memory loss. This can be a slight loss of memory that does not affect daily life. Or it could be dementia, which also changes how well you can think and plan. Alzheimer's disease is a type of dementia.
  • Infections in the brain and spinal cord, such as encephalitis or meningitis.
  • Stroke.
  • Seizures.

How can you avoid nervous system problems?

  • Do not smoke. If you need help quitting, talk to your doctor about stop-smoking programs and medicines. These can increase your chances of quitting for good.
  • Do not use drugs. And limit alcohol to 2 drinks a day for men and 1 drink a day for women. Too much alcohol can cause health problems.
  • Take care of health problems that may harm your nervous system. These include diabetes and high blood pressure.
  • Learn new skills, which can increase your attention span and how well you can focus.
  • Be safe with medicines. Read and follow all directions on the label.
  • Protect yourself from head injuries and falls. For example, wear a helmet when you bike, skate, or ski. Use grab handles and nonskid mats in the tub and shower.

The Health Encyclopedia contains general health information. Not all treatments or services described are covered benefits for Kaiser Permanente members or offered as services by Kaiser Permanente. For a list of covered benefits, please refer to your Evidence of Coverage or Summary Plan Description. For recommended treatments, please consult with your health care provider.